Sector Capacity Assessment Methodology

ATFM• Airspace Capacity

Airspace capacity is not unlimited but it can be more or less optimized depending on many factors,such as:

Airspace design and flexibility. ATC system capacity. Number of sectors and their complexity. Segregated airspace. Availability, training, and response capability of personnel. Available CNS infrastructure. Degree of automation. The equipage and type of aircraft in the fleet.

When analyzing airspace capacity, we are interested in focusing on ATC system capacity and, in thissense, we have highlighted some concepts that must be taken into account as indicators to calculate the ATCsector capacity, such as: workload, the importance of observable and non-observable tasks performed by airtraffic controllers.

ATFM• Air Traffic Flow Management

The purpose of ATFM is to achieve abalance between air traffic demand and airspacecapacity to ensure an optimum safe and efficient useof airspace.

In order to manage this demand-capacitybalance, it is necessary to know the current andexpected demand, to establish a capacity baselineusing an analytical calculation, to analyse the impactthat expected demand will have on existing capacity,to identify the limitations of, and possibleimprovements to, the current system based on acost/benefit analysis thereof, to set priorities, and todevelop a capacity improvement plan.

ATC• ACC Sectors

1. North L2. East L3. North East L4. CTA West5. CTA East6. West7. Central8. South9. South East

ACC Sectors

Jeddah

1. North U2. East U3. North East U4. CTA Upper5. CTA Lower

ACC Sectors

Riyadh

RiyadhJeddah

FL345

Capacity• Sector Capacity Equation And

Methodology

N The number of aircraft that can be controlled simultaneously by a single ATCO

ϕThe ATCO availability factor (expressed as a %), defined as the percentage of timeavailable for planning aircraft separation procedures (more information about thisparameter is provided in the Airspace and Capacity Management Manual, p. 63-64)

TAverage flight time of the aircraft in the sector (the unit of time needs to be the same asfor τm below - the conversion is done automatically in this tool)

ηNumber of communications for each aircraft in the sector, which must be limited to theleast possible number required for an understanding between the pilot and the ATCO

τmMean duration of each message (the unit of time needs to be the same as for T above -the conversion is done automatically in this tool)

𝑵 =𝝋 ∙ 𝑻

𝜼 ∙ 𝝉𝒎

Note: All the above figures based on field assessments.(T) is based on fast time simulation.

Capacity• Field assessment figures based on sector operation -

Riyadh

Riyadh Center

ACC Sector Number of transmit Average duration per transmit

Controller Availability

ATCO ATCO+PLNR

ACC-N 6 6 50% 70%

ACC-E 5 5 50% 70%

ACC-NE 5 5 50% 70%

APU 5 6 50% 70%

It is important for data collection to be significant so as to dilute temporary stochasticdeviations and to represent reliable values for the ATC unit.

According to the current model, controller workload is the summation of times spent on:1. Communication (transmission/reception);2. Manual activities (updating out flight progress strips) and coordination3. Traffic planning and distribution.

Equation and Methodology• availability factor (φ)

Defined as the percentage of time available for the ATCO to plan aircraft separation procedures.

This availability factor normally falls between a minimum value of 40% of ATCO time for non-radar control, and 60% forradar control. It is thus clear that efforts need to focus on increasing the “availability factor” φ.The latter can only be achieved by applying measures to reduce the level of controller intervention in the activitiesmentioned in 1 and 2. (Previous slid)

The percentage accounted for by this φ factor could increase if the “Human Machine Interface –HMI” is enhanced; thatis, when increasing the level of automation in some tasks.

Studies conducted by experts, who analyzed the sampling techniques, show that it is advisable to make at least 25observations of each parameter for average controller, during peak traffic, respecting the minimum number ofcontrollers specified by the sampling technique used.

It is essential to collect as many observations and controllers as possible in the unit being assessed in orderto eliminate extreme values and to minimize any type of trend (e.g., cases of controllers or pilots who areeither too slow or too quick in their communications, affecting the arithmetical mean).

ATFCM• Current Measures and Future Plan

• CMC – FUA (End 2019)• CNS|ATM Infrastructure Plan• Airspace Restructure• Re-sectorization (Dynamic Sectors)• ATFCM

• Sector Capacity ( ACCs-TMAs)• Runway Capacity• AD Capacity• IFPS (Q1 2020)• ATFM System

• Activate the flow management if agreed with adjacent centers.• Coordinate departure with ATS units.• Activate the planner position.• Airspace Changes.• Active the maestro position (Hajj)

Current

Future

Thank You!